Registration of GA R01‐40‐08, a Gossypium hirsutum Upland Cotton Germplasm Line with qFL‐Chr.1 Introgressed from Gossypium barbadense Conferring Improved Fiber Length

Abstract

GA R01‐40‐08 (Reg. no. GP‐1060, PI 690433), is a Gossypium hirsutum L. germplasm line developed by the Molecular Cotton Breeding Laboratory, Department of Crop and Soil Sciences, at the University of Georgia. GA R01‐40‐08 was selected from an interspecific backcross inbred population derived from the cross of ‘Tamcot 2111’ (G. hirsutum) with ‘Pima S‐6’ (G. barbadense L.). This G. hirsutum germplasm line harbors an introgressed quantitative trait locus (QTL), qFL‐Chr.1, conferring improved upper half mean fiber length (UHML) from Pima S‐6. Field trials conducted in Plains and Tifton, GA, in 2009, 2013, and 2014 indicate that GA R01‐40‐08 exhibits improved UHML of 1.5 mm longer than the Tamcot 2111 parent, representing a 5% improvement. GA R01‐40‐08 had fiber yields over 18% higher than the Pima S‐6 parent and equivalent to the higher‐yielding parent, Tamcot 2111. This germplasm line represents a milestone in upland cotton germplasm improvement as the first publicly released germplasm line carrying a fiber length QTL with an effect that has been validated in multiple environments. It will provide upland cotton breeders with an adapted source of the qFL‐Chr.1 QTL for improved UHML from G. barbadense, and the tightly linked markers published previously will allow breeders to use marker‐assisted selection for rapid incorporation.